An intraoral controller prototype is being developed and tested that may provide a control channel for spinal cord injured individuals (C5 level or above). This two-axis prototype is an analog controller mounted on a palatal splint. A two-dimensional control signal is generated by tongue contraction and movement. integrated EMG signals are measured by anterior-posterior and right-left pairs of sensors in a diamond configuration on the tongue side of the splint. Multipurpose discrete control signals are also generated by two jaw-activated microswitches located on the lateral aspects of the splint. The purpose of Phase II of this project is to complete development of the equipment and software to adequately test and optimize the responsiveness of this prototype and define the number of levels of control signal discrimination for two axes. Prototype systems will be tested in high level spinal cord injured individuals and in therapists at two institutions to complete a small pilot study of this technology. These systems will be used to emulate a computer mouse using auditory and visual feedback. Other uses of this intraoral controller might include control of a neuroprosthesis for functional neuromuscular stimulation, a limb prothesis, or an orthosis. PROPOSED COMMERCIAL APPLICATION: An intraoral controller would represent a new form of technology for both quadriplegics and non-impaired individuals. The potential market may be quite large. An intraoral controller might interact more quickly with its operator than hand or foot controllers. It may be useful in environments where heavy protective clothing and gloves must be worn or during activities occupying both hands.